'Shark Tank' stars dive into Discovery's Shark Week for charity

“It’s time for a Shark to meet sharks,” Daymond John, an entrepreneur from ABC's "Shark Tank," declares before jumping in the water with the real thing.

So Wednesday, he and the other fast-talking investor tycoons trade their natty business attire for wetsuits in Discovery's "Shark Tank Meets Shark Week" special (9 EDT/PDT).

John, the founder of the Fubu clothing line; venture capitalist Kevin O’Leary; New York real-estate maven Barbara Corcoran; and Dallas Mavericks owner Mark Cuban spend time with nonprofits around the world devoted to shark conservation. Then each tries to convince the others why his or her team deserves a $50,000 donation.

“It’s the Wild West out there,” he tells his fellow Sharks. “There are a lot of dive operators out there, and we need to create a code for them."

In an interview, he ticks off a list of questions the group wants to answer in its guidelines: “Is it OK for the divers to touch the sharks? The sharks may get too accustomed to humans. How many people are in the water per shark? How many security divers do you need? Do you chum the water? How long do you stay down? How close to the shore do you go?”

But before he can get in the tank, a wardrobe dilemma has to be solved: He wants to dive sporting his signature black suit, an idea the aquarium rejects.

“I said, ‘I don’t mind sacrificing a suit, but I’m swimming with those whale sharks in my suit; otherwise, people won’t recognize me,' ” O’Leary recalls, only to be informed he can't go into the water wearing something that hasn't been approved or sterilized. "So I told them, ‘That’s your problem. I’m wearing a suit in there, so you go figure it out.’ "

The solution: A custom wetsuit, approximating a white shirt, black tie, lapels and even a pocket square. “I think it’s hilarious,” O’Leary declares. But once he gets in the water and sees a whale shark with a tail the size of a 747 approaching him, he admits, “I wet my wetsuit!”

Putting aside O'Leary's fun day at the aquarium, Corcoran asks why whale-shark research is worthy of outside funding.

“We’re trying to figure out, 'Are these fish being damaged by their environment?' " O'Leary tells her in the special. "Is there something we should learn about how their health is changing? You tag them so you know where they are. Then you start to understand their behavior, so you maybe know where not to let boats go when they’re migrating."

John and O’Leary say the Shark Week episode has made them more excited to fund environmentally friendly product pitches from contestants.

“I’m never buying plastic straws again,” O’Leary vows after seeing the damage they do to the oceans. “I’m going to make sure everybody I’m sitting at a table with doesn’t use them, either. ... There must be a better way. Some entrepreneur is going to solve that.”